Rosa M Covarrubias

US Patent:

6770170, Aug 3, 2004

Filed:

Mar 9, 2001

Appl. No.:

09/803225

Inventors:

Rosa Maria Covarrubias - Bartlett TN

Assignee:

Buckman Laboratories International, Inc. - Memphis TN

International Classification:

D21H 1100

US Classification:

1621641, 1621643, 1621646, 1621681, 1621682, 1621683, 1621811, 1621814, 1621815, 162183

Abstract:

Methods of making paper or paperboard are described. According to one method, fibrous cationic colloidal alumina microparticles and a polymer are introduced to a papermaking pulp to form a treated pulp having improved retention properties. The fibrous cationic colloidal alumina microparticles are preferably a fibrous cationic acetate salt of boehmite alumina having a zeta potential of greater than about 25 and a weight ratio of alumina to acetate of less than about 4. The polymer can be a cationic polymer, a nonionic polymer, an amphoteric polymer under cationic conditions, or combinations thereof. The pulp may also be treated with at least one coagulant, at least one flocculant, at least one cationic starch, at least one cellulytic enzyme, and/or other conventional papermaking pulp additives. The resulting pulp is formed into a sheet of pulp and then drained to form a paper or paperboard. Other papermaking processes are also described as is a papermaking apparatus for carrying out the methods.

US Patent:

8308900, Nov 13, 2012

Filed:

Sep 12, 2007

Appl. No.:

11/853859

Inventors:

Rosa M. Covarrubias - Memphis TN, US
Budi Liputra - Jakarta Barat, ID

Assignee:

Buckman Laboratories International, Inc. - Memphis TN

International Classification:

D21C 3/22

US Classification:

162 70, 162 72, 162158, 435278

Abstract:

Methods to control lipophilic extractives in pulp and fibers are described. One method involves contacting the pulp or fibers with a composition containing at least one enzyme, such as at least one esterase or lipase or both, for a sufficient time and in a sufficient amount to control the lipophilic extractives present in the pulp or fibers.

US Patent:

8454798, Jun 4, 2013

Filed:

Apr 14, 2011

Appl. No.:

13/086889

Inventors:

Weiping Ban - Memphis TN, US
Gary Headrick - Memphis TN, US
Rosa M. Covarrubias - Memphis TN, US

Assignee:

Buckman Laboratories International, Inc. - Memphis TN

International Classification:

D21H 23/14
D21H 17/00
D21H 17/28
D21H 17/33
D21H 17/45
D21H 17/56
D21H 17/66
D21F 1/66

US Classification:

162183, 162 72, 1621641, 1621646, 1621682, 1621683, 162158, 162175, 1621812

Abstract:

A method is described for making paper or paper board by applying a composition containing enzyme and cationic coagulant to papermaking pulp prior to paper forming to preferably improve drainage, retention, or both. Sheets of pulp from which paper or paperboard products are made with the method can exhibit excellent drainage, excellent retention of pulp fines, or both. The method also can be applied to other pulp treatments, such as waste water treatments. A system for making such treatments of paper furnish is also provided.

US Patent:

20020033245, Mar 21, 2002

Filed:

May 17, 2001

Appl. No.:

09/860023

Inventors:

Mohan Karve - Memphis TN, US
Rosa Covarrubias - Bartlett TN, US
Gerald Dykstra - Bartlett TN, US
Saleem Mirza - Bartlett TN, US

International Classification:

D21H017/67
D21F001/00

US Classification:

162/181500, 162/183000, 162/289000

Abstract:

Methods of making paper or paperboard are described. According to one of the methods, an acidic aqueous alumina sol is introduced to a papermaking pulp to form a treated pulp having improved retention properties. The acidic aqueous alumina sol preferably has a pH of from about 3 to about 6. The sol preferably contains elongate secondary particles which are elongated from about 50 nm to about 300 nm in only one plane and formed by edge-to-edge coagulation of rectangular plate like primary particles having a length on one side of from about 10 nm to about 30 nm when observed through an electron microscope. The pulp may also be treated with at least one coagulant, at least one flocculent, at least one cationic starch, at least one cellulytic enzyme, at least one biocide, and/or other conventional papermaking pulp additives. The resulting pulp is formed into a sheet of pulp and then drained to form a paper or paperboard. Other papermaking processes are also described as is a papermaking apparatus for carrying out the methods. Paper and paperboard containing dried pulp that has been treated with an acidic aqueous alumina sol are also described. Methods to flocculate particulate materials in a dispersion are also described.

US Patent:

20050161183, Jul 28, 2005

Filed:

Jan 21, 2005

Appl. No.:

11/040579

Inventors:

Rosa Covarrubias - Bartlett TN, US

International Classification:

D21H017/74

US Classification:

162158000, 162164100, 162181600, 162168300, 162183000

Abstract:

Methods for making paper or paperboard are described. One preferred method comprises forming a treated pulp by added to a papermaking pulp a synthetic layered silicate, a peptizer and at least one polymer. The synthetic layered silicate preferably comprises a synthetic hydrous sodium lithium magnesium silicate and the polymer is selected from cationic, nonionic and amphoteric polymers. The peptizer is preferably an inorganic polyphosphate peptizer and is contained in certain commercial synthetic layered silicate products. The inventor has surprisingly found that the peptizer provides significant improvements in drainage, retention and turbidity, thereby improving the papermaking process and the paper or paperboard product.

US Patent:

20070169903, Jul 26, 2007

Filed:

Jan 24, 2007

Appl. No.:

11/657306

Inventors:

Rosa M. Covarrubias - Memphis TN, US
Gary A. Headrick - Memphis TN, US
Alan B. Rosenberg - Lakeland TN, US

International Classification:

D21H 17/29
D21H 21/30
D21H 23/02
D21H 17/00
D21H 21/00

US Classification:

162158, 162175, 162162, 162183

Abstract:

A method of making paper or paperboard is described, which includes introducing at least one charged starch, preferably having a degree of substitution greater than 0.045, and at least one optical brightening agent to a papermaking pulp and then forming the pulp into paper or paperboard. The present invention further describes methods of improving optical brightener performance.

US Patent:

20190360922, Nov 28, 2019

Filed:

May 17, 2019

Appl. No.:

16/414875

Inventors:

- Memphis TN, US
Rosa COVARRUBIAS - Memphis TN, US
Hannes MONSTREY - Eke, BE

International Classification:

G01N 21/27
G01N 21/59
G01N 21/78
G01N 33/34

Abstract:

In a starch concentration measurement, a liquid sample is conducted from a liquid sample such as pulp suspension or filtrate of a paper, board or tissue process. An iodine solution is added to the sample, and a light absorbance or transmittance of the sample is measured at a target wavelength. The measured absorbance or transmittance of the sample is then converted into the starch concentration of the sample.

US Patent:

20150159329, Jun 11, 2015

Filed:

Dec 5, 2014

Appl. No.:

14/561235

Inventors:

- Memphis TN, US
Daniel E. Glover - Brighton TN, US
Rosa Covarrubias - Memphis TN, US

Assignee:

Buckman Laboratories International, Inc. - Memphis TN

International Classification:

D21H 21/14
D21H 17/00
C09J 103/08

Abstract:

A formulation useful as a creping adhesive formulation or Yankee dryer coating composition is described. Methods of creping using the formulation are also described.